The present invention relates to the measurement of small lags or differences in arrival times between a signal edge and an instant of reference preferably defined by another signal edge.
Such time lags or delays are generally measured by the processing of information elements acquired by direct sampling on the edge of the incident signal or on the edges of the incident signals. Such measurement entails major difficulties when time differences of the order of some nanoseconds or even of one nanosecond are to be detected, and when the edge or edges of the incident signals are short and liable to local deformations which are a cause of errors.
The present invention is aimed at enabling the measurement of very short time lags on one or more signal edges by getting rid of a certain number of faults related to the direct temporal exploitation of the signal edges.
To do so, it is proposed to reduce a time measurement to a phase-shift measurement by using a signal edge to prepare two components in quadrature of a rotating vector in which the passage of time is expressed by a linear phase variation.